Triazapentadienes as acaricides

ABSTRACT

Certain heteroaryl triazapentadienes with acaricidal properties and their preparation are described.

CROSS REFERENCE TO RELATED APPLICATION

This application is a division of application Ser. No. 787,084 filed Apr. 13, 1977, now U.S. Pat. No. 4,128,652.

BACKGROUND OF THE INVENTION

All stages in the life cycle of ticks tend to damage the skins of afflicted animals and thereby spoil the state of the skins with the consequence that cattle hides and sheep skins intended for the manufacture of leather and sheep skin are reduced in quality. Furthermore, the ticks may facilitate the transmission of disease to the afflicted animal, and the general state of health and the quality of flesh of the animal may be detrimentally affected.

Belgian Pat. No. 816,760 describes certain 5-(substituted phenyl)-3-(alkyl)-1-(alkyl)-1,3,5-triazapenta-1,4-dienes as broad spectrum parasiticides.

We have now found that certain 5-(substituted phenyl)-3-methyl-1-(heteroaryl)-triazapenta-1,4-dienes have particularly useful acaricidal properties, and are thus very useful in destroying one or more stages in the life cycle of ticks which tend to infest the skins of animals such as cattle. They may also have insecticidal properties, particularly against plant insects such as pea aphids (hemiptera).

SUMMARY OF THE INVENTION

This invention is concerned with triazapentadienes of the formula: ##STR1## wherein R¹ is a C₁ -C₄ alkyl group;

R² is a hydrogen atom, a halogen atom or a C₁ -C₄ alkyl group;

R³ is a monocyclic or bicyclic heteroaryl group attached to the adjacent nitrogen atom by a carbon atom of said group; and

R⁴ is a hydrogen atom or a C₁ -C₄ alkyl group;

and the acid addition salts of the compounds of the formula (I) which form such salts.

DETAILED DESCRIPTION OF THE INVENTION

In this specification the term "halogen" means fluorine, chlorine, bromine or iodine.

Alkyl groups containing three or more carbon atoms may be straight or branched chain. The preferred alkyl groups contain 1 or 2 carbon atoms.

R¹ is preferably a methyl group.

R² is preferably a methyl group or a chlorine atom.

R² is most preferably methyl.

Generally, the preferred heteroaryl groups within the scope of R³ are those including at least one ring nitrogen atom, such as quinolyl, isoquinolyl, pyridyl, pyrimidinyl, quinazolinyl, quinoxalinyl, tetrazolyl, thiazolyl, benzothiazolyl, 4,5,6,7-tetrahydrobenzothiazolyl, thiadiazolyl, indazolyl, oxazolyl, benzoxazolyl, pyridazinyl and pyrazinyl. However, benzothienyl is also a preferred heteroaryl group within the scope of R³.

The heteroaryl group represented by R³ may be substituted or unsubstituted. Preferred substituents are C₁ -C₆ alkyl, C₁ -C₆ alkoxy, di(C₁ -C₄ alkoxy) methyl, (C₁ -C₄ alkoxy) carbonyl, halogen, trifluoromethyl, phenyl, and C₂ -C₅ alkanoyl. Preferred alkoxy groups contain 1 or 2 carbon atoms and preferred alkanoyl groups 2 or 3 carbon atoms.

The more preferred heteroaryl groups are quinolyl, isoquinolyl, pyridyl, quinoxalinyl, pyridazinyl, pyrimidinyl, pyrazinyl, indazolyl, tetrazolyl, thiazolyl, benzothiazolyl, 4,5,6,7-tetrahydrobenzothiazolyl and benzothienyl optionally containing one or two substituents selected from C₁ -C₄ alkyl, C₁ -C₄ alkoxy, phenyl, di(C₁ -C₄ alkoxy) methyl, (C₁ -C₄ alkoxy)carbonyl and halogen.

The most preferred heteroaryl groups are thiazolyl, pyridyl, quinolyl, pyrazinyl, pyridazinyl, quinoxalinyl, benzothiazolyl and benzothienyla optionally containing one or two substituents selected from halogen, C₁ -C₄ alkyl and C₁ -C₄ alkoxy.

R⁴ is preferably a hydrogen atom.

The preferred individual compounds are as follows:

5-(2,5-dimethylphenyl)-3-methyl-1-(2-thiazolyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(2-pyridyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-quinolyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-ethyl-6-methyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-ethyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-methyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(2,5-dimethyl-pyrid-3-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(2-chloro-pyrid-3-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(2-pyrazinyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(6-methoxy-pyridazin-3-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(6-quinolyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(6-quinoxalinyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3,6-dimethyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3,5-dimethyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-n-propyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3-n-butyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(6-benzothiazolyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(6-benzothienyl)-1,3,5-triazapenta-1,4-diene

5-(2,4-dimethylphenyl)-3-methyl-1-(3,4-dimethyl-pyrid-2-yl)-1,3,5-triazapenta-1,4-diene.

The compounds of the invention may be prepared via a number of routes, including the following:

(1) Compounds in which R⁴ is hydrogen may be prepared by reacting a formamidine of the formula: ##STR2## with an isonitrile of the formula R³.NC. R¹, R² and R³ are as defined for formula (I).

The reaction may be effected in the presence of a suitable catalyst, most preferably finely divided copper metal or a cuprous catalyst such as cuprous oxide or cuprous chloride in a trace amount, a typical reaction temperature being 50° to 80° C. Increased reaction temperatures are not generally recommended because they tend to increase the formation of by-products due to the reaction of one molecule of compound (II) with another such molecule. The reaction may be effected in the presence of a suitable inert organic solvent, such as benzene or toluene.

Generally, long reaction times are necessary unless finely divided copper metal is used as the catalyst.

Typically, the product is recovered by evaporation of the reaction mixture in vacuo to leave an oil which may, if necessary, be purified by a conventional procedure such as treatment with neutral alumina in 40°-60° petroleum ether. The purified oil may crystallise on standing to give crystals of the desired product of the formula (I).

The isonitriles of the formula R³.NC and the formamidines of the formula (II) are either known compounds or may be prepared by procedures analogous to those of the prior art. Methods for the preparation of formamidines falling within the formula (II) are described for example in British Patent Specifications Nos. 964,640, 1,039,930 and 1,327,936.

(2) The following route, in which R⁴ may be hydrogen or C₁ -C₄ alkyl, is also possible:

an imidate of the formula: ##STR3## wherein R¹ and R² are as defined for formula (I) and R⁵ is a C₁ -C₄ alkyl group, is reacted with an amidine of the formula: ##STR4## wherein R³ and R⁴ are as defined for formula (I).

(3) Compounds of the formula (I) in which R⁴ is a hydrogen atom or a C₁ -C₄ alkyl group may be prepared by reacting an amidine of the formula: ##STR5## wherein R³ and R⁴ are as defined for formula (I), with an isonitrile of the formula: ##STR6## wherein R¹ and R² are as defined for formula (I).

The reaction and isolation of the product may be carried out in a similar manner to method (1) above, although in this case it is generally possible to use reaction temperature of above 80° C. without substantially increasing the formation of by-products, reaction generally being substantially complete within 4-8 hours at 100° C. except when using finely divided copper metal as the catalyst in which case the reaction is generally complete in 1-2 hours.

This is a preferred route. The starting materials of the formula (IV) are either known compounds or may be obtained in a conventional manner, e.g. as follows: ##STR7##

(4) The compounds of the formula (I) in which R⁴ is a hydrogen atom or a C₁ -C₄ alkyl group may also be prepared by reacting a formamidine of the formula: ##STR8## wherein R¹ and R² are as defined for formula (I), with an imidate of the formula: ##STR9## wherein R³ and R⁴ are as defined for formula (I) and R⁶ is a C₁ -C₄ alkyl group. R⁶ is preferably an ethyl group.

The reaction is typically carried out by heating the reactants together for several hours, e.g. at 40°-100° C. for 2-4 hours. Alternatively a solvent, e.g. iso-octane, may be used. The product typically crystallises on cooling and may be purified by crystallisation from e.g. hexane, cyclohexane or mixed solvents, e.g. methylene chloride/hexane. Treatment with decolouring carbon during crystallisation may be beneficial.

This is a preferred route.

The imidates of the formula (VI) are either known compounds or may be obtained in a conventional manner, e.g. as follows: ##STR10##

(5) The acid-addition salts of the compounds of the formula (I) which form such salts may be made in a conventional manner, e.g. by mixing a solution of the free base in a suitable solvent, e.g. diethyl ether, with a solution of the appropriate acid in a suitable solvent, e.g. diethyl ether, and recovering the salt as a precipitate.

The compounds of the formula (I) have acaricidal activity, particularly against all stages in the life cycle, including gravid female ticks, of the cattle ticks Boophilus microplus, Haemaphysalis longicornus, Phipicephalus appendiculatus and Boophilus decoloratus.

In one test, five freshly collected, fully engorged Boophilus microplus adult female ticks are used for each acaricidal compound. Using a micro-pipette 10 micro-liters of a solution containing 10 micro-grams of the acaricidal compound in ethanol or acetone, is applied to the dorsal surface of each of the ticks. The treated ticks are placed in weighed 1"×2" glass vials, weighed and stored at 26° C. and 80%+R.H. in plastic boxes for two weeks. The ticks are then removed from the vials and the vials weighed to give the weight of eggs laid by the ticks. Any reduction in the egg laying of the treated ticks is calculated as a percentage of the eggs laid by untreated control ticks.

The eggs are returned to the incubator for a further 3 weeks after which time the percentage of eggs hatching is estimated.

The percentage reduction in the anticipated reproduction of the ticks is calculated using the weight of eggs laid and the percentage of eggs hatching.

The test may be repeated using smaller amounts of the acaricidal compound.

In another test, using a pipette 0.5 ml of a solution containing 0.5 mg of the acaricidal compound in ethanol or acetone is spread evenly on to a Whatman No. 1 filter paper 8 cm×6.25 cm (50 sq. c.m.) to give a dosage of 100 mg/m².

The treated paper is allowed to dry at room temperature, folded with the treated surface inside and two short edges sealed with a crimping machine. The open ended envelope is placed in a 1 lb Kilner jar containing damp cotton wool in a plastic pot and stored in an incubator at 26° C. for 24 hours. 20-50 Boophilus microplus larvae, which had hatched 8-14 days previously, are placed in the envelope using a small spatula. The open end is then crimped to form a sealed packet. The treated paper containing the larvae is returned to the Kilner jar and kept for a further 48 hours in the incubator. 20-50 larvae are placed similarly in an untreated paper envelope to act as controls. At the end of the 48 hour test period the mortality is noted and recorded as a percentage after correction for any mortality among the untreated control ticks.

The test may be repeated using smaller amounts of the acaricidal compound.

In addition to percentage effectiveness figures, ED₅₀ results can be obtained from dose response measurements using any of the afore-described tests.

Activity against Haemaphysalis longicornus nymphs may be measured in a similar manner to the above larvae test.

The activity of certain of the compounds of the Examples detailed hereinafter against the tick Boophilus microplus is set out in the following Table:

                  TABLE                                                            ______________________________________                                         Boophilus Microplus (in vitro)                                                                   Adult (Topical)                                                                             %                                               Larva (Contact)                Reduction                                       Compound                                                                               Dose                Dose     in Egg                                    No.     (mg/m.sup.2)                                                                               % Kill  (μg/tick)                                                                            Hatch                                     ______________________________________                                          1            100       100       10     100                                   and 90        12.5      100       2      99                                     2            100       100       10     99                                    and 91        6.25      100       4      93                                     3            100       100       10     99                                                  12.5      94        2      96                                     4            100       100       10     100                                                 12.5      100       2      97                                     5            100       100       10     100                                                 12.5      100       4      88                                     6            100       100       10     100                                                 6.25      100       4      86                                     7            100       100       10     89                                                  12.5      100                                                     8            100       100       10     90                                                  25        100                                                     9            100       100       10     53                                                  25        86                                                     10            100       100       10     92                                                  25        89                                                     11            100       100       10     92                                                  6.25      100                                                    12            100       78        --     --                                    13            100       31        8      68                                    14            100       100       10     100                                                 3.13      90        4      97                                    15            100       100       10     100                                                 3.13      100       4      83                                    16            100       100       10     100                                   and 92        3.13      98        2      95                                    17            100       100       10     100                                                 6.25      100       2      67                                    18            100       56        10     100                                   and 76                            4      99                                    20            100       100       10     29                                                  12.5      100                                                    21            100       86        10     58                                    22            100       90        10     99                                                                      4      97                                    23            100       100       10     85                                                  12.5      100                                                    24            100       100       10     100                                                 12.5      83        2      90                                    25            100       100       10     100                                                 12.5      88        2      91                                    26            100       100       10     100                                                 25        98        8      98                                    27            100       85        10     53                                    28            100       100       10     100                                                 50        98        2      99                                    29            100       100       2      20                                                  50        82                                                     30            100       100       10     78                                                  25        92                                                     31            100       100       10     94                                                  6.25      83                                                     32            100       17        10     59                                    33            100       33        10     100                                                                     4      98                                    34            100       100       10     93                                    35            100       100       10     13                                                  25        83                                                     36            100       100       10     16                                    37            100       32        10     100                                                                     4      90                                    38            100       100       10     72                                                  6.25      94                                                     39            100       100       10     96                                                  12.5      98                                                     40            100       14        8      100                                                                     4      81                                    41            100       100       10     100                                   42            100       100       10     25                                                  12.5      100                                                    43            100       97        10     100                                                 12.5      100                                                    44            100       100       10     97                                                  6.25      84                                                     45            100       100       10     100                                                 6.25      100                                                    46            100       100       10     22                                    47            100       100       10     28                                    48            100       92        10     100                                                                     8      91                                    50            100       100       10     95                                                  25        100       8      94                                    51            100       100       10     93                                    52            100       100       10     18                                                  50        100                                                    54            100       80        10     55                                    55            100       100       10     26                                                  12.5      100                                                    56            100       100       10     85                                                  25        73                                                     57            100       80        10     89                                    58            100       97        10     96                                                  25        79                                                     59            100       100       10     66                                                  25        68                                                     60            100       94        10     28                                                  25        88                                                     62            100       98        10     88                                                  50        60                                                     63            100       100       10     7                                                   12.5      100                                                    65            100       100       10     100                                                 12.5      76        1      97                                    66            100       100       10     100                                                 --        --        1      90                                    67            100       84        10     98                                                  --        --        4      58                                    68            100       69        10     100                                                 --        --        4      84                                    69            100       24        10     99                                    70            100       100       10     100                                                 3.12      95        1      31                                    71            100       85        10     89                                                  --        --        4      57                                    72            100       100       10     99                                                  1.56      73        2      22                                    73            100       100       10     91                                                  12.5      100       2      69                                    74            100       66        10     99                                                  --        --        4      52                                    77            100       100       10     100                                                 12.5      89        2      71                                    78            100       91        10     100                                                                     2      97                                    79            100       100       10     100                                                 50        33        1      83                                    80            100       59        10     100                                                                     2      98                                    83            100       85        10     100                                                                     1      97                                    ______________________________________                                    

Thus the invention also provides an acaricidal composition comprising a compound of the formula (I) together with a diluent or carrier. The diluent or carrier may be a solid or a liquid, optionally together with an antioxidant, dispersing agent, emulsifying agent or wetting agent. The compositions of the invention include not only compositions in a suitable form for application but concentrated primary compositions which may be supplied to the user and which require dilution with a suitable quantity of water or other diluent prior to application. Typical compositions of the invention include, for example, dusting powders, dispersible powders, dispersions, emulsions and emulsifiable concentrates.

A dust may be made by mixing the appropriate amount of the finely divided active compound with a solid pulverent diluent or carrier such as talc, clay, calcite, pyrophyllite, diatomaceous earth, walnut shell flour, silica gel, hydrated alumina, or calcium silicate. As an alternative method of preparation, the diluent or carrier is mixed with a solution of the active compound in a volatile organic solvent such as benzene, the solvent being subsequently removed by evaporation. Typically, the active compound will be present in the dust in an amount of from 0.25 to about 4% by weight.

Dispersible powders may be made by adding a suitable dispersing agent to the active compound, or to a dust containing the active compound, so that a stable aqueous dispersion of the active compound is formed on mixing the powder with water. The dispersible powders preferably contain from about 25 to 75% by weight of the active compound.

Emulsifiable concentrates comprise a solution of the active compound in a substantially water-immiscible non-toxic organic solvent containing an emulsifying agent. Suitable solvents include, for example, toluene, xylene, petroleum oil, and alkylated naphthalenes. Preferably, the concentrate will contain 5-75 gms. of the active compound per 100 ml. of solution. The concentrates may be diluted with water prior to use to give a typical concentration of the active compound in the aqueous medium of from e.g. about 0.001 to about 0.1% w/v (g/100 ml.), or approximately 10 to 1000 p.p.m. The volatile solvents, e.g. toluene and xylene, evaporate after spraying to leave a deposit of the active ingredient. The made up spray or dip will generally be an emulsion.

The compositions of the invention may be applied to ground, such as that around dairies, in order to combat e.g. cattle ticks thereon. However, it is preferred to treat animals by spraying them or passing them through animal dips.

Thus the present invention also provides a method for protecting animals, particularly cattle, from acarids, particularly cattle ticks, which comprises treating the animal externally with an acaricidal amount of a compound of the formula (I) or acaricidal composition as defined above.

The compositions of the invention may also contain a pesticide, fungicide, additional acaricide, or the like.

The invention is illustrated by the following Examples, in which all temperatures are given in °C. The compounds of the invention were characterised by infra-red and nuclear magnetic resonance (n.m.r.) spectra, thin layer chromatography, and, in most cases, by melting point, analytical and mass spectral data. In the n.m.r. data, the protons responsible for the signals are underlined, s, q, t and m indicating, respectively, a singlet, quartet, triplet and multiplet.

EXAMPLE 1 Preparation of 5-(2,4-dimethylphenyl)-3-methyl-1-(2-pyridyl)-1,3,5-triazapenta-1,4-diene ##STR11##

A mixture of N-methyl-N'-(2-pyridyl)-formamidine (2.5 g, 0.0185 m), 2,4-dimethylphenylisocyanide (2.4 g, 0.0185 m), cuprous oxide (trace amount) and dry toluene (60 ml) was heated on a steam bath with occasional agitation for 4 hours. The reaction mixture was then cooled, filtered through "Hyflo" (diatomaceous earth) and alumina, and the toluene filtrate evaporated to dryness in vacuo to yield a viscous oil. The oil was triturated with 60°-80° petroleum ether to yield a white solid. Crystallisation of this solid from ether/60°-80° petroleum ether yielded the product, 5-(2,4-dimethylphenyl)-3-methyl-1-(2-pyridyl)-1,3,5-triazapenta-1,4-diene, (1.0 g) m.p. 100°.

Analysis %: Found: C, 71.84% H, 6.52; H, 20.59. C₁₆ H₁₈ N₄ requires: C, 72.15; H, 6.81; H, 21.04.

EXAMPLES 2 TO 75

The following compounds were prepared by procedures similar to that of Example 1, starting from 2,4-dimethylphenylisocyanide or 4-chloro-2-methylphenylisocyanide and the appropriate amidine of the formula R³.N═C(R⁴).NHCH₃.

    __________________________________________________________________________      ##STR12##                                                                

    __________________________________________________________________________                                       Analysis %                                                                     (Theoretical in brackets)                                                 m.p. C      H      N                              Compound No.                                                                           R.sup.2                                                                             R.sup.3     R.sup.4                                                                            (° C.)                                                                       (or n.m.r. and mass spectral                 __________________________________________________________________________                                       data)                                        2       CH.sub.3                                                                           ##STR13##    H   76-79                                                                               71.68 (71.83                                                                          6.71 6.63                                                                             16.88 16.75)*                  3       CH.sub.3                                                                           ##STR14##    H   86-88                                                                               71.79 (72.15                                                                          6.96 6.81                                                                             20.36 21.07)                   4       CH.sub.3                                                                           ##STR15##    H   115-116                                                                             73.00 (73.44                                                                          7.45 7.53                                                                             18.76 19.03)                   5       CH.sub.3                                                                           ##STR16##    H   98   63.77 (63.87                                                                          5.51 5.78                                                                             18.85 18.63)                    *this compound was isolated as the monohydrate, and the theoretical            analysis calculated accordingly.                                              6       CH.sub.3                                                                           ##STR17##    H   104-5                                                                               71.98 (72.15                                                                          6.79 6.81                                                                             20.97 21.07)                   7       Cl                                                                                 ##STR18##    H   112  62.64 (62.82                                                                          5.12 5.27                                                                             19.19 19.54)                   8       Cl                                                                                 ##STR19##    H   138-140                                                                             63.02 (62.82                                                                          5.11 5.27                                                                             19.27 19.54)                   9       Cl                                                                                 ##STR20##    H   84-86                                                                               56.05 (56.09                                                                          4.04 4.39                                                                             17.30 17.44)                   10      Cl                                                                                 ##STR21##    H   93-96                                                                               58.72 (58.87                                                                          5.50 5.52                                                                             15.93 16.16)                   11      Cl                                                                                 ##STR22##    H   75-79                                                                               62.70 (62.82                                                                          5.35 5.27                                                                             20.09 19.54)                   12      CH.sub.3                                                                           ##STR23##    CH.sub.3                                                                           oil                                                                                  ##STR24##                                   13      CH.sub.3                                                                           ##STR25##    C.sub.2 H.sub.5                                                                    oil                                                                                  ##STR26##                                   14      CH.sub.3                                                                           ##STR27##    H   125  64.15 (63.90                                                                          5.63 5.66                                                                             18.68 18.64)                   15      Cl                                                                                 ##STR28##    H   152  56.49 (56.07                                                                          4.44 4.36                                                                             17.78 17.45)                   16      CH.sub.3                                                                           ##STR29##    H   80   74.08 (74.00                                                                          7.89 7.84                                                                             18.11 18.17)                   17      Cl                                                                                 ##STR30##    H   85   65.61 (65.74                                                                          6.49 6.44                                                                             16.91 17.04)                   18*     CH.sub.3                                                                           ##STR31##    H   99-100                                                                              61.36 (61.74                                                                          5.81 5.92                                                                             21.18 20.57)                    *This experiment was repeated under similar conditions but using a trace       amount of finelydivided copper metal in place of cuprous oxide as the          catalyst.  -                                                                  19      CH.sub.3                                                                           ##STR32##    H   133-136                                                                             67.72 (67.05                                                                          5.69 5.63                                                                             17.52 17.38)                   20      CH.sub.3                                                                           ##STR33##    H   151-153                                                                             57.01 (57.32                                                                          4.85 4.81                                                                             16.72 16.71)                                                     Analysis %                                                                     (Theoretical in brackets)                                                 m.p. C                                            Compound No.                                                                           R.sup.2                                                                             R.sup.3     R.sup.4                                                                            (°C.)                                                                        (or n.m.r.)                                                                           H      N                              __________________________________________________________________________     21      CH.sub.3                                                                           ##STR34##    H   129-131                                                                             69.40 (69.58                                                                          6.11 6.12                                                                             15.50 15.46)                   22      CH.sub.3                                                                           ##STR35##    H   96-98                                                                               76.02 (75.92                                                                          6.32 6.37                                                                             17.85 17.71)                   23      Cl                                                                                 ##STR36##    H   110  67.88 (67.75                                                                          5.01 5.09                                                                             16.75 16.63)                   24      CH.sub.3                                                                           ##STR37##    H   129-130                                                                             73.25 (73.44                                                                          7.53 7.53                                                                             19.25 19.03)                   25      CH.sub.3                                                                           ##STR38##    H   104-5                                                                               71.85 (71.90                                                                          5.88 6.03                                                                             21.53 22.07)                   26      Cl                                                                                 ##STR39##    H   132-4                                                                               63.89 (64.00                                                                          4.78 4.77                                                                             20.67 20.73)                   27      CH.sub.3                                                                           ##STR40##    CH.sub.3                                                                           76-8 73.77 (73.99                                                                          7.75 7.84                                                                             18.02 18.17)                   28      CH.sub.3                                                                           ##STR41##    H   150-151                                                                             64.59 (64.63                                                                          6.30 6.44                                                                             23.03 55)                                                        n.m.r. (CDCl.sub.3)                          29      Cl                                                                                 ##STR42##    CH.sub.3                                                                           Oil                                                                                  ##STR43##                                   30      Cl                                                                                 ##STR44##    H   62-4 53.22 (53.33                                                                          4.52 4.48                                                                             19.52 19.14)                   31      Cl                                                                                 ##STR45##    H   128-9                                                                               58.24 (58.44                                                                          4.88 4.90                                                                             24.16 24.34)                   32      CH.sub.3                                                                           ##STR46##    CH.sub.3                                                                           100-101                                                                             67.24 (67.04                                                                          7.07 7.11                                                                             16.52 16.46)                   33      Cl                                                                                 ##STR47##    H   130-131                                                                             59.52 (59.56                                                                          4.39 4.41                                                                             16.40 16.34)                   34      Cl                                                                                 ##STR48##    C.sub.2 H.sub.5                                                                    70   64.71 (64.86                                                                          6.09 6.08                                                                             17.40 .80)                     35      CH.sub.3                                                                           ##STR49##    CH.sub.3                                                                           142  72.86 (72.83                                                                          7.28 7.19                                                                             20.18 19.98)                   36      Cl                                                                                 ##STR50##    CH.sub.3                                                                           97   63.63 (63.89                                                                          5.76 5.57                                                                             18.74 18.63)                   37      CH.sub.3                                                                           ##STR51##    H   129-130                                                                             67.41 (67.19                                                                          6.23 6.41                                                                             25.56 26.20)                   38      Cl                                                                                 ##STR52##    H   148  56.29 (56.69                                                                          5.01 5.07                                                                             21.83 22.04)                   39      CH.sub.3                                                                           ##STR53##    C.sub.2 H.sub.5                                                                    85   73.16 (73.44                                                                          7.70 7.53                                                                             18.75 19.03)                   40      CH.sub.3                                                                           ##STR54##    H   69-72                                                                               67.45 (67.79                                                                          7.07 7.17                                                                             17.40 17.50)                   41      Cl                                                                                 ##STR55##    H   Oil                                                                                  ##STR56##                                   42      CH.sub.3                                                                           ##STR57##    H   134-5                                                                               68.57 (68.94                                                                          5.90 5.79                                                                             15.96 16.08)                   43      CH.sub.3                                                                           ##STR58##    H   107-8                                                                               63.14 (62.91                                                                          6.27 6.33                                                                             19.78 19.81)                   44      Cl                                                                                 ##STR59##    H   108-9                                                                               61.47 (61.87                                                                          4.64 4.65                                                                             15.43 15.19)                   45      Cl                                                                                 ##STR60##    H   Oil                                                                                  ##STR61##                                   46      Cl                                                                                 ##STR62##    CH.sub.3                                                                           96-97                                                                               54.83 (54.81                                                                          4.93 4.93                                                                             18.00 18.06)                   47      CH.sub.3                                                                           ##STR63##    CH.sub.3                                                                           105  62.66 (62.91                                                                          6.39 6.34                                                                             20.17 19.56)                   48      Cl                                                                                 ##STR64##    H   87-9 54.46 (54.81                                                                          4.88 4.93                                                                             17.80 18.26)                   49      CH.sub.3                                                                           ##STR65##    CH.sub.3                                                                           --   --     --     --                             50      CH.sub.3                                                                           ##STR66##    CH.sub.3                                                                           68-70                                                                               64.31 (63.97                                                                          6.87 6.71                                                                             19.32 18.65)                   51      Cl                                                                                 ##STR67##    CH.sub.3                                                                           77-8 55.96 (56.15                                                                          5.53 5.34                                                                             21.07 17.46)                   52      CH.sub.3                                                                           ##STR68##    CH.sub.3                                                                           99   67.90 (68.30                                                                          6.85 6.81                                                                             24.29 24.00)                   53      Cl                                                                                 ##STR69##    CH.sub.3                                                                           124  59.30 (59.70                                                                          5.34 5.34                                                                             23.13 23.21)                   54      CH.sub.3                                                                           ##STR70##    CH.sub.3                                                                           145  65.04 (65.57                                                                          7.02 6.80                                                                             22.24 22.46)                   55      Cl                                                                                 ##STR71##    CH.sub.3                                                                           149-150                                                                             57.54 (57.92                                                                          5.73 5.47                                                                             21.61 21.00)                   56      Cl                                                                                 ##STR72##    H   53   50.96 (51.07                                                                          5.10 5.28                                                                             32.57 32.07)                   57      CH.sub.3                                                                           ##STR73##    H   86   58.76 (58.93                                                                          6.97 6.71                                                                             35.40 34.36)                   58      CH.sub.3                                                                           ##STR74##    H   126-128                                                                             63.90 (63.97                                                                          6.67 6.71                                                                             18.26 18.65)                   59      Cl                                                                                 ##STR75##    H   120-122                                                                             56.14 (56.15                                                                          5.31 5.34                                                                             17.53 17.46)                   60      CH.sub.3                                                                           ##STR76##    CH.sub.3                                                                           112-114                                                                             64.44 (64.94                                                                          6.92 7.05                                                                             17.64 17.82)                   61      Cl                                                                                 ##STR77##    CH.sub.3                                                                           135-6                                                                               57.22 (57.39                                                                          5.65 5.72                                                                             16.64 16.73)                   62      CH.sub.3                                                                           ##STR78##    H   121-122                                                                             59.11 (59.28                                                                          6.00 5.85                                                                             16.67 16.27)                   63      Cl                                                                                 ##STR79##    H   110-111                                                                             62.79 (62.74                                                                          4.78 5.00                                                                             14.57 14.63)                   64      Cl                                                                                 ##STR80##    CH.sub.3                                                                           90-92                                                                               62.82 (63.54                                                                          5.41 5.33                                                                             13.95 13.11)                   65      CH.sub.3                                                                           ##STR81##    H   84-86                                                                               72.66 (72.83                                                                          7.12 7.19                                                                             19.98 19.98)                   66      CH.sub.3                                                                           ##STR82##    H   105-107                                                                             72.51 (72.83                                                                          7.08 7.19                                                                             19.82 19.98)                   67      Cl                                                                                 ##STR83##    H   92-94                                                                               63.36 (63.89                                                                          5.90 5.70                                                                             18.81 18.63)                   68      CH.sub.3                                                                           ##STR84##    H   146-147                                                                             75.52 (75.92                                                                          6.49 6.37                                                                             18.08 17.71)                   69      CH.sub.3                                                                           ##STR85##    H   87-89                                                                               73.04 (72.83                                                                          7.40 7.19                                                                             20.21 19.98)                   70      Cl                                                                                 ##STR86##    H   103-4                                                                               64.21 (63.89                                                                          5.82 5.70                                                                             19.01 18.63)                   71      Cl                                                                                 ##STR87##    H   124-5                                                                               67.66 (67.75                                                                          5.24 5.09                                                                             16.60 16.63)                   72      Cl                                                                                 ##STR88##    H   129-130                                                                             63.78 (63.89                                                                          5.77 5.70                                                                             19.01 18.63)                   73      CH.sub.3                                                                           ##STR89##    H   122-5                                                                               72.94 (72.83                                                                          7.13 7.19                                                                             20.78 19.98)                   74      Cl                                                                                 ##STR90##    H   99.5- 101.5                                                                         64.42 (63.89                                                                          5.75 5.70                                                                             18.66 18.63)                   75      CH.sub.3                                                                           ##STR91##    H   Oil  n.m.r.: δ = 1.23 (t, 6H),                                                2-CH.sub.2 CH.sub.3 ; 2.30 (s, 6H) 2                                           aromatic CH.sub.3 groups; 3.53 (s) N .                                         CH.sub.3. Molecular weight from mass                                           spectral data <07.                           __________________________________________________________________________

EXAMPLE 76 Preparation of 5-(2,4-Dimethylphenyl)-3-methyl-1-(2-thiazolyl)-1, 3,5-triazapenta-1,4-diene ##STR92## A mixture of N-methyl-N'-(2,4-dimethylphenyl)-formamidine (188.8 g) and ethyl N-(2-thiazolyl)-formimidate (200.0 g) was heated to 75° for 2 hours under water-pump pressure. Ethanol began to distil shortly after heating commenced and ceased after approximately 1 hour. On cooling, the mixture solidified. Crystallisation from n-hexane and recrystallisation from methylene chloride/hexane with decolourising carbon treatment afforded 295 g of product in two crops. (Yield 93%). A portion was further recrystallised from cyclohexane to provide an analytical sample, m.p. 101°.

Analysis %: Found: C, 61.62; H, 5.96; N, 21.23. Calculated for C₁₄ H₁₆ N₄ S: C, 61.73; H, 5.92; N, 20.57%.

The product was identical to the product of Example 18.

EXAMPLE 77-93

The following compounds were prepared similarly to Example 76, starting from N-methyl-N'-(2,4-dimethylphenyl)formamidine and the appropriate formimidate of the formula R³.N═CH.OC₂ H₅.

    __________________________________________________________________________      ##STR93##                                                                                                 Analysis %                                                                     (Theoretical in brackets)                          Compound                m.p.                                                                               C                                                  No.   R.sup.2                                                                           R.sup.3      R.sup.4                                                                          (°C.)                                                                       (or n.m.r.)                                                                          H     N                                      __________________________________________________________________________     77    CH.sub.3                                                                           ##STR94##   H 134-5                                                                              67.00 (67.39                                                                         6.28 6.41                                                                            27.03 26.20)                           78    CH.sub.3                                                                           ##STR95##   H 89  76.34 6.32 6.37                                                                            17. 7 17.71)                           79    CH.sub.3                                                                           ##STR96##   H 64-5                                                                               n.m.r. (CDCl.sub.3) δ = 2.26 (s, 6H), 2                                  aromatic CH.sub.3 groups; 3.43 (s, 3H),                                        NCH.sub.3. Molecular weight from mass                                          spectral data 3.21                                                             This compound was a monohydrate.                   80    CH.sub.3                                                                           ##STR97##   H oil 63.51 5.70 5.92                                                                             15.51  16.46)                                                      Molecular weight from mass spectral                                           data 322.                                          81    CH.sub.3                                                                           ##STR98##   H 135 66.04 (66.23                                                                         6.71 6.79                                                                            17.24 17.16)                           82    CH.sub.3                                                                           ##STR99##   H 97-8                                                                               73.14 (73.44                                                                          7.63 7.53                                                                           19.  19.03)                            83    CH.sub.3                                                                           ##STR100##  H 91-3                                                                               75.51 (73.44                                                                         7.37 7.53                                                                            18.87 19.03)                           84    CH.sub.3                                                                           ##STR101##  H 148- 150                                                                           57.31 (57.32                                                                         4.56 4.81                                                                             .79 16.71)                            85    CH.sub.3                                                                           ##STR102##  H 129 55.62 (55.66                                                                         4.85 4.96                                                                            16.22 16.23)                           86    CH.sub.3                                                                           ##STR103##  H 104 73.05 (73.44                                                                         7.40 7.53                                                                            1 .98 19.03)                           87    CH.sub.3                                                                           ##STR104##  H 70-71                                                                               ##STR105##                                                                           ##STR106##                                                                           ##STR107##                            88    CH.sub.3                                                                           ##STR108##  H 135-6                                                                               ##STR109##                                                                           ##STR110##                                                                           ##STR111##                            89    CH.sub.3                                                                           ##STR112##  H 52-3                                                                                ##STR113##                                                                           ##STR114##                                                                           ##STR115##                            90    CH.sub.3                                                                           ##STR116##  H 101                                                                                 ##STR117##                                                                           ##STR118##                                                                           ##STR119##                            91    CH.sub.3                                                                           ##STR120##  H 76-79                                                                               ##STR121##                                        92    CH.sub.3                                                                           ##STR122##  H 79-80                                                                               ##STR123##                                                                           ##STR124##                                                                           ##STR125##                            93    CH.sub.3                                                                           ##STR126##  H 91                                                                                  ##STR127##                                                                           ##STR128##                                                                           ##STR129##                            __________________________________________________________________________      The products of Examples 90 to 92 were identical to the products of            Examples 1,2 and 16 respectively.                                        

EXAMPLE 94

The constituents of an emulsifiable concentrate are as follows:

    ______________________________________                                         5-(2,4-Dimethylphenyl)-3-methyl-1-                                             (2-pyridyl)-1,3,5-triazapenta-1,4-diene                                                              5-75% w/v                                                Emulsifier(s)         up to 20% w/v                                            Antioxidant(s)        up to 0.1%                                               Mixed hydrocarbon solvent                                                                            balance to 100%                                          ______________________________________                                    

The concentrate is prepared by mixing the emulsifier(s), antioxidant(s) and solvent until homogeneous, adding the triazapentadiene and stirring until dissolution occurs.

Preparation of Starting Materials

The following examples, in which all temperatures are in °C., illustrate the preparation of certain of the starting materials:

EXAMPLE I ##STR130##

A solution of 3-aminoquinoline (5.8 g, 0.04 m) in dry ether was treated with hydrogen chloride gas and the resulting monohydrochloride salt obtained by filtration. A suspension of this salt and p-toluenesulphonyl chloride (7.2 g, 0.038 m) in N-methylformamide (30 ml) was stirred at room temperature for 30 minutes then warmed to 90° on a steam bath. After 1 hour, the resulting yellow suspension was cooled and poured into acetone (100 ml), and the insoluble solid filtered off. The solid was then dissolved in water, the resulting solution basified with ION NaOH solution, and the resulting solid extracted into chloroform. The chloroform extract was dried and the solvent removed in vacuo to yield an almost colourless solid which crystallised from chloroform/40°-60° petroleum ether to give N-methyl-N'-(3-quinolyl)-formamidine, (5.5 g, 95%) of m.p. 142°-143°.

Analysis: Found: C, 71.08; H, 5.78; N, 22.99%. Required for C₁₁ H₁₁ N₃ : C, 71.30; H, 5.98; N, 22.67%.

EXAMPLES II TO V

The following formamidines were prepared by procedures similar to that of Example I, starting with N-methylformamide and the appropriate amine of the formula R³.NH₂.

    __________________________________________________________________________     R.sup.3 . NCHNH . CH.sub.3                                                                              n.m.r. or                                                                      Analysis %                                                                m.p. (Theoretical in brackets)                             Compound                                                                             R.sup.3       (°C.)                                                                        C    H    N                                           __________________________________________________________________________     II                                                                                    ##STR131##   oil  n.m.r. (CDCl.sub.3): δ = 3.00 (s, N .                                    CH.sub.3), 6.3 (s, NH . CH.sub.3) 7.66 (s,                                     NCHN).                                                III                                                                                   ##STR132##   142-144                                                                             66.07 (66.23                                                                        8.17 8.03                                                                           25.19 25.74)                                IV                                                                                    ##STR133##   106-9                                                                               49.37 (49.57                                                                        4.61 4.75                                                                           24.62 24.77)                                       ##STR134##   105-6                                                                               54.67 (55.37                                                                        6.52 6.71                                                                           21.30 21.52)                                __________________________________________________________________________

EXAMPLE VI ##STR135##

A solution of 3-aminopyridine (20.0 g, 0.21 m) in excess triethyl orthoformate (100 ml) and ethanolic hydrogen chloride (0.3 ml) was heated under reflux for 72 hours. Ethanol and excess triethyl orthoformate were then removed by distillation over a period of 5 hours. Solid potassium carbonate (100 mg) was added to the residue, and the last traces of triethyl orthoformate were removed in vacuo. The residue was then distilled under reduced pressure to yield the desired imido ester, ethyl N-(3-pyridyl)-formimidate, as a colourless liquid, (b.p. 62°/0.5 mm) (24 g, 75%), n.m.r. (CDCl₃): δ=1.4 (t, --CH₂ CH₃), 4.32 (q, --CH₂ CH₃), 7.73 (s, --N═CH--O).

The preparation of this compound is also described in J. Prakt. Chem., 313, 179 (1971). ##STR136##

The imido ester prepared in part (a) above was added to a solution of methylamine in ethanol (33% w/w) at -10°, and the resulting solution was then allowed to attain room temperature (25°). After standing overnight, the solvent and excess methylamine were removed at 40° in vacuo to yield the N-methyl-N'-(3-pyridyl) formamidine (15 g) as a colourless liquid. n.m.r. (CDCl₃); δ=3.00 (s, --N.CH₃), 7.66 (S, --N--CH--N).

The preparation of this compound is also described in J. Prakt. Chem., 314, 627 (1972).

EXAMPLES VII TO LVIII

The following imido esters were prepared by procedures similar to that of Example VI part (a), starting from the appropriate amine of the formula R³.NH₂ and ester of the formula R⁴.C(OC₂ H₅)₃.

    __________________________________________________________________________      ##STR137##                                                                                                B.P.                                               Compound                                                                             R.sup.3         R.sup.4                                                                              (°C.)                                                                           n.m.r.                                     __________________________________________________________________________     VII*                                                                                  ##STR138##     H     60°/2mm                                                                         n.m.r. (CDCl.sub.3): δ = 1.4                                             (t, CH.sub.2 CH.sub.3), 4.40 (q,                                               CH.sub.2 CH.sub.3), 8.32 (s, NCHO)         VIII*                                                                                 ##STR139##     H     66°/ 0.5 mm                                                                     n.m.r. (CDCl.sub.3): δ = 1.35                                            (t, CH.sub.2 CH.sub.3), 4.35 (q,                                               CH.sub.2 CH.sub.3), 7.72 (s, NCHO)         IX                                                                                    ##STR140##     CH.sub.3                                                                             64°/ 0.5 mm                                                                     n.m.r. (CDCl.sub.3): δ = 1.35                                            (t, CH.sub.2 CH.sub.3), 4.25 (q,                                               CH.sub.2 CH.sub.3), 1.87 (s, CCH.sub.                                          3)                                                ##STR141##     C.sub.2 H.sub.5                                                                      70°/ 0.4 mm                                                                     n.m.r. (CDCl.sub.3): δ = 1.35                                            (t, OCH.sub.2 CH.sub.3), 4.25 (q,                                              OCH.sub.2 CH.sub.3), 2.15 (q,                                                  CCH.sub.2 CH.sub.3), 1.10 (t, C .                                              CH.sub.2 CH.sub.3)                         XI*                                                                                   ##STR142##     H     66°/ 0.1 mm                                                                     n.m.r. (CDCl.sub.3): δ = 1.38                                            (t, CH.sub.2 CH.sub.3), 4.35 (q,                                               CH.sub.2 CH.sub.3), 8.32 (s, NCHO)         XII                                                                                   ##STR143##     H     60°/ 0.1 mm                                                                     n.m.r. (CDCl.sub.3): δ = 1.4                                             (t, OCH.sub.2 CH.sub.3), 4.38 (q,                                              OCH.sub.2 CH.sub.3), 8.25 (s, NCHO)        XIII                                                                                  ##STR144##     H     120°/ 0.22 mm                                                                   n.m.r. (CDCl.sub.3): δ = 1.4                                             (t, CH.sub.2 CH.sub.3), 4.4 (q,                                                CH.sub.2 CH.sub.3), 7.7 (s, NCHO)          XIV                                                                                   ##STR145##     H     56°/ 0.08 mm                                                                    n.m.r. (CDCl.sub.3): δ = 1.25                                            (t, CH.sub.2 CH.sub.3), 4.30 (q,                                               CH.sub.2 CH.sub.3), 8.3 (s, NCHO)          XV                                                                                    ##STR146##     H     60°- 62° (m.p.)                                                          n.m.r. (CDCl.sub.3): δ = 1.4                                             (t, CH.sub.2 CH.sub.3), 4.45 (q,                                               CH.sub.2 CH.sub.3), 8.4 (s, NCHO)          XVI                                                                                   ##STR147##     CH.sub.3                                                                             88° @ 0.2 mm                                                                    n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          H.sub.2 CH.sub.3) 4.25 (q, CH.sub.2                                            CH.sub.3) 2.1 (s, CCH.sub.3)               XVII                                                                                  ##STR148##     H     165° @ 0.05 mm                                                                  n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          CH.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                            CH.sub.3) 1.2 (t, [OCH.sub.2 CH.sub.3                                          ].sub.2) 3.65 (q, [OCH.sub.2 CH.sub.3                                          ].sub.2)                                   XVIII                                                                                 ##STR149##     H     MPt. 85°                                                                        n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          CH.sub.2 CH.sub.3) 4.4 (q, CH.sub.2                                            CH.sub.3)                                  XIX                                                                                   ##STR150##     CH.sub.3                                                                             145° @  0.3 mm                                                                  n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          H.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                             CH.sub.3) 2.2 (s, CCH.sub.3)               XX                                                                                    ##STR151##     CH.sub.3                                                                             78° @ 0.1 mm                                                                    n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          H.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                             CH.sub.3) 2.2 (s, CCH.sub.3)               XXI                                                                                   ##STR152##     CH.sub.3                                                                             54°-6° @ 0.1 mm                                                          n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          H.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                             CH.sub.3) 2.0 (s, CCH.sub.3)               XXII                                                                                  ##STR153##     H     143°-7° @ 0.3                                                            n.m.r. (CDCl.sub.3) δ  = 1.4                                             (t, CH.sub.2 CH.sub.3) 4.4 (q,                                                 CH.sub.2 CH.sub.3) 8.45 (s, NCHO)          XXIII                                                                                 ##STR154##     CH.sub.3                                                                             MPt. 81°-2°                                                              n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3) 4.3 (q,                                                 CH.sub.2 CH.sub.3) 2.0 (s,                                                     CCH.sub.3)                                 XXIV                                                                                  ##STR155##     H     87°-8° @ 2 mm                                                            n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3) 4.4 (q,                                                 CH.sub.2 CH.sub.3)                         XXV                                                                                   ##STR156##     CH.sub.3                                                                             86°-8° @ 0.1 mm                                                          n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3) 4.25 (q,                                                CH.sub.2 CH.sub.3) 1.85 (s,                                                    CCH.sub.3)                                 XXVI                                                                                  ##STR157##     H      156°-62° @ 0.05                                                         n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          CH.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                            CH.sub.3) 8.4 (s, NCHO)                    XXVII                                                                                 ##STR158##     CH.sub.3                                                                             57°-60° @ 0.01                                                           n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          CH.sub.2 CH.sub.3) 4.25 (q, CH.sub.2                                           CH.sub.3) 1.8 (s, CCH.sub.3)               XXVIII                                                                                ##STR159##     H     74° @ 0.1 mm                                                                    n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          CH.sub.2 CH.sub.3) 4.4 (q, CH.sub.2                                            CH.sub.3) 8.3 (s, NCHO)                    XXIX                                                                                  ##STR160##     CH.sub.2 CH.sub.3                                                                    57°-60° @ 0.1                                                            n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          OCH.sub.2 CH.sub.3) 4.3 (q, OCH.sub.2                                          CH.sub.3) 1.1 (t, CCH.sub.2 CH.sub.3)                                          .5 (q, CCH.sub.2 CH.sub.3)                 XXX                                                                                   ##STR161##     H     86°-90° @ 0.2                                                            n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          CH.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                            CH.sub.3) 8.1 (s, NCHO)                    XXXI                                                                                  ##STR162##     CH.sub.3                                                                             60° @ 0.1 mm                                                                    n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          CH.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                            CH.sub.3) 2.1 (s, CCH.sub.3)               XXXII                                                                                 ##STR163##     CH.sub.3                                                                             142°-4° @ 0.35                                                           n.m.r. (CDCl.sub.3) δ = 1.3 (t,                                          CH.sub.2 CH.sub.3) 4.3 (q, CH.sub.2                                            CH.sub.3) 2.2 (s, CCH.sub.3)               XXXIII                                                                                ##STR164##     H     86°  @ 0.02 mm                                                                  n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          CH.sub.2 CH.sub.3) 4.4 (q, CH.sub.2                                            CH.sub.3) 8.4 (s, NCHO)                    XXXIV                                                                                 ##STR165##     H     136° @ 0.1 mm                                                                   n.m.r. (CDCl.sub.3) δ = 1.4 (t,                                          CH.sub.2 CH.sub.3) 4.35 (q, CH.sub.2                                           CH.sub.3) 8.1 (s, NCHO)                    XXXV                                                                                  ##STR166##     H     156°- 160° @ 0.03                                                        n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3) 4.35 (q,                                                CH.sub.2 CH.sub.3) 8.3 (s, NCHO)           XXXVI                                                                                 ##STR167##     CH.sub.3                                                                             96°-100° @ 0.025                                                         n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3)  4.25 (q,                                               CH.sub.2 CH.sub.3) 1.8 (s,                                                     CCH.sub.3)                                 XXXVII                                                                                ##STR168##     H     76°-82° @ 0.05                                                           n.m.r. (CDCl.sub.3) δ = 1.35                                             (t, CH.sub.2 CH.sub.3) 4.3 (q,                                                 CH.sub.2 CH.sub.3)  7.65 (s, NCHO)         XXXVIII                                                                               ##STR169##     H     88°-90° @ 0.4                                                            (C, H and N analyses - theoretical in                                          brackets) 42.97 6.58 41.62 (42.60                                              6.55 41.39)                                XXXIX                                                                                 ##STR170##     H     150°-2° @ 0.01                                                           n.m.r. δ = 7.80 (s, NCH); 4.30                                           (q, OCH.sub.2 CH.sub.3) 1.35 (t,                                               OCH.sub.2 CH.sub.3) 3.50 (q,                                                   CH(OCH.sub.2 CH.sub.3).sub.2); 1.18                                            (t, CH(OCH.sub.2 CH.sub.3).sub.2.                                              Molecular wt. from mass spectra 291.       XL                                                                                    ##STR171##     H     82° @ 0.75 mm                                                                   n.m.r. (CDCl.sub.3) δ = 8.24                                             (s, NCHO), 4.40 (q, OCH.sub.2                                                  CH.sub.3); 8.3 (s, ArCH.sub.3 ; 1.4                                            (t, OCH.sub.2 CH.sub.3).                   XLI                                                                                   ##STR172##     H     70°-72° @ 0.4                                                            n.m.r. (CDCl.sub.3) δ = 8.23                                             (s, NCHO); 4.39 (q, OCH.sub.2                                                  CH.sub.3); = 2.5 (s, ArCH.sub.3);                                              1.39 (t, OCH.sub.2 CH.sub.3).              XLII                                                                                  ##STR173##     H     90°-92° @ 0.6-0.7                                                        n.m.r. (CDCl.sub.3) δ = 8.31                                             (s, N CHO); 4.40 (q, OCH.sub.2                                                 CH.sub.3); = 2.34 (s, ArCH.sub.3);                                             1.40 (t, OCH.sub.2 CH.sub.3).              XLIII                                                                                 ##STR174##     H     80°-82° @ 0.7                                                            n.m.r. (CDCl.sub.3) δ = 8.3 (s,                                          HO); 4.28 (q, OCH.sub.2 CH.sub.3); =                                           2.18 (s, ArCH.sub.3); 1.29 (t,                                                 OCH.sub.2 CH.sub.3).                       XLIV                                                                                  ##STR175##     H     128° @ 0.05 mm                                                                  n.m.r. (CDCl.sub.3) δ = 8.41                                             (s, NCHO); 4.52 (q, OCH.sub.2                                                  CH.sub.3); = 1.46 (t, OCH.sub.2                                                CH.sub.3).                                 XLV                                                                                   ##STR176##     H     84° @ 0.5 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.58                                             (s, NCHO); 4.48 (q, OCH.sub.2                                                  CH.sub.3); = 1.38 (t, OCH.sub.2                                                CH.sub.3).                                 XLVI                                                                                  ##STR177##     H     132° @ 0.4 mm                                                                   n.m.r. (CDCl.sub.3) δ = 7.8 (s,                                          HO); 4.4 (q, OCH.sub.2 CH.sub.3); =                                            1.4 (t, OCH.sub.2 CH.sub.3).               XLVII                                                                                 ##STR178##     H     70° @ 0.4 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.16                                             (s, NCHO); 4.36 (q, OCH.sub.2                                                  CH.sub.3) = 2.42 (s, ArCH.sub.3);                                              2.21 (s, ArCH.sub.3); = 1.36 (t,                                               OCH.sub.2 CH.sub.3).                       XLVIII                                                                                ##STR179##     H     66° @ 0.3 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.39                                             (s, NCHO); 4.52 (q, OCH.sub.2                                                  CH.sub.3) = 2.56-3.09 (m, ArCH.sub.2                                           CH.sub.3); 1.55 (t, ArCH.sub.2                                                 CH.sub.3); = 1.39 (t, OCH.sub.2                                                CH.sub.3).                                 XLIX                                                                                  ##STR180##     H     72° @ 0.1 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.34                                             (s, NCHO); 4.55 (q,                                                            CH.sub.2 CH.sub.3); = 1.55 (t,                                                 CH.sub.2 CH.sub.3).                        L                                                                                     ##STR181##     H     75°-80° @ 0.2                                                            n.m.r. (CDCl.sub.3) δ = 8.32                                             (s, NCHO); 4.35 (q,                                                            CH.sub.2 CH.sub.3); = 1.35 (t,                                                 CH.sub.2 CH.sub.3).                        LI                                                                                    ##STR182##     H     93° @ 0.2 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.29                                             (s, NCHO); 4.38 (q, OCH.sub.2                                                  CH.sub.3) = 1.39 (t, OCH.sub.2                                                 CH.sub.3 ).                                LII                                                                                   ##STR183##     H     60°-62° (m.p.)                                                           n.m.r. (CDCl.sub.3) δ = 8.44                                             (s, NCHO); 4.45 (q, OCH.sub.2                                                  CH.sub.3); = 1.4 (t, OCH.sub.2                                                 CH.sub.3).                                 LIII                                                                                  ##STR184##     H     100°-120° @ 14                                                           n.m.r. (CDCl.sub.3) δ = 8.2 (s,                                          HO); 4.30 (q, OCH.sub.2 CH.sub.3); =                                           2.16 (s, ArCH.sub.3); 1.29 (t,                                                 CH.sub.2 CH.sub.3).                        LIV                                                                                   ##STR185##     H     127° @ 0.5 mm                                                                   n.m.r. (CDCl.sub.3) δ = 7.7 (s,                                          HO); 4.3 (q, OCH.sub.2 CH.sub.3); =                                            1.3 (q, OCH.sub.2 CH.sub.3).               LV                                                                                    ##STR186##     H     93° @ 0.2 mm                                                                    n.m.r. (CDCl.sub.3) δ = 8.29                                             (s, NCHO); 4.38 (q, OCH.sub.2                                                  CH.sub.3); = 1.39 (t, OCH.sub.2                                                CH.sub.3).                                 LVI                                                                                   ##STR187##     H     86°-88° @ 0.4                                                            n.m.r. (CDCl.sub.3) δ = 8.24                                             (s, NCHO); 3.57 (q, OCH.sub.2                                                  CH.sub.3); = 2.2 (s, 2 Aromatic                                                CH.sub.3 's); = 1.2 (t, OCH.sub.2                                              CH.sub.3).                                 LVII                                                                                  ##STR188##     H     102°-104° @ 0.25                                                         n.m.r. (CDCl.sub.3) δ =7.96 (s,                                          HO); 4.52 (q, OCH.sub.2 CH.sub.3);                                             1.4 (t, OCH.sub.2 CH.sub.3).               LVIII                                                                                 ##STR189##     H     102° @ 0.1 mm                                                                   n.m.r. (CDCl.sub.3) δ  = 7.66                                            (s, NCHO); 4.28 (q, OCH.sub.2                                                  CH.sub.3); 1.32 (t, OCH.sub.2                                                  CH.sub.3).                                 __________________________________________________________________________     *the preparation of these compounds are also described in T. Prakt. Chem.,      313, 179 (1979).

EXAMPLE LIX TO XCVI

The following amidines were prepared by procedures similar to that of Example VI part (b), starting from the appropriate imido ester of the formula R³.N═C(R⁴)OC₂ H₅ and methylamine.

    __________________________________________________________________________      R.sup.3 . NC(R.sup.4) . NHCH.sub.3                                                                         n.m.r. or Analysis %                                                     M.P.  (Theoretical in brackets)                         Compound                                                                             R.sup.3       R.sup.4                                                                           (°C.)                                                                         CHN                                               __________________________________________________________________________     LIX                                                                                   ##STR190##   H  --    n.m.r.(CDCl.sub.3): δ = 2.95 (s, N .                                     CH.sub.3), 8.45 (s, NCHN)                         LX                                                                                    ##STR191##   H  --    n.m.r. (CDCl.sub.3): δ = 3.02 (s, N .                                    CH.sub.3), 7.80 (s, NCHN)                         LXI                                                                                   ##STR192##   CH.sub.3                                                                          --    n.m.r. (CDCl.sub.3): δ = 2.85 (s, N .                                    CH.sub.3), 1.80 (s, NCCH.sub.3), 6.3 (s,                                       NHCH.sub.3)                                       LXII                                                                                  ##STR193##   C.sub.2 H.sub.5                                                                   --    n.m.r. (CDCl.sub.3): δ  = 2.90 (s, N .                                   CH.sub.3), 2.20 (q, CH.sub.2 CH.sub.3, 1.05                                    (t, CH.sub.2 CH.sub.3)                            LXIII                                                                                 ##STR194##   H  112°                                                                          n.m.r. (CDCl.sub.3): δ = 3.02 (s, N .                                    CH.sub.3), 8.42 (s, NCHN)                         LXIV                                                                                  ##STR195##   H  --    n.m.r. (CDCl.sub.3): δ = 3.00 (s, N .                                    CH.sub.3), 8.35 (s, NCHN)                         LXV                                                                                   ##STR196##   H  134-5°                                                                        40.963.4220.87 (41.203.4620.59)                   LXVI                                                                                  ##STR197##   H  84-85°                                                                        42.705.0929.69 (42.545.0029.76)                   LXVII                                                                                 ##STR198##   H  132°                                                                          n.m.r. (CDCl.sub. 3): δ = 3.10 (s, N .                                   CH.sub.3), 8.40 (s, NCHN)                         LXVIII                                                                                ##STR199##   CH.sub.3                                                                          129-130°                                                                      63.866.4616.63 (63.646.1617.13)                   LXIX                                                                                  ##STR200##   H  129-131°                                                                      49.636.4025.09 (49.686.5524.83)                   LXX                                                                                   ##STR201##   H  oil   n.m.r. (CDCl.sub.3) δ = 3.0 (s,                                          NHCH.sub.3) 7.9 (s, NCHNH) 1.2 (t,                                             [OCH.sub.2 CH.sub.3 ].sub.2) 3.6 (q,                                           [OCH.sub.2 CH.sub.3 ].sub.2)                      LXXI                                                                                  ##STR202##   H  MPt. 118°                                                                     n.m.r. (CDCl.sub. 3) δ = 3.05 (s,                                        NHCH.sub.3)                                       LXXII                                                                                 ##STR203##   CH.sub.3                                                                          101-3°                                                                        62.855.7718.44 (62.315.6618.17)                   LXXIII                                                                                ##STR204##   CH.sub.3                                                                          60-2°                                                                         49.626.4425.39 (49.686.5524.83)                   LXXIV                                                                                 ##STR205##   H  Oil   n.m.r. (CDCl.sub.3) δ = 3.0 (s,                                          NHCH.sub.3)                                       LXXV                                                                                  ##STR206##   C.sub.2 H.sub.5                                                                   BPt. 90° @ 0.04 mm                                                            n.m.r. (CDCl.sub.3) δ = 2.95 (d,                                         NHCH.sub.3) 1.25 (t, CCH.sub.2 CH.sub.3) 2.4                                   (q, CCH.sub.2 CH.sub.3)                           LXXVI                                                                                 ##STR207##   CH.sub.3                                                                          BPt. 90° @ 0.03 mm                                                            n.m.r. (CDCl.sub.3) δ = 3.1 (d,                                          NHCH.sub.3) 2.9 (s, CCH.sub.3)                    LXXVII                                                                                ##STR208##   CH.sub.3                                                                          78°                                                                           46.255.9126.74 (46.435.8527.07)                   LXXVIII                                                                               ##STR209##   H  106-8°                                                                        61.315.1718.98 (60.805.1019.34)                   LXXIX                                                                                 ##STR210##   H  129-131°                                                                      46.816.0727.38 (46.435.8427.07)                   LXXX                                                                                  ##STR211##   H  145-6°                                                                        61.995.5218.16 (62.315.6618.17)                   LXXXI                                                                                 ##STR212##   CH.sub.3                                                                          153-6°                                                                        67.668.6024.20 (67.768.5323.71)                   LXXXII                                                                                ##STR213##   H  81-82°                                                                        39.086.5654.57 (38.956.5454.51)                   LXXXIII                                                                               ##STR214##   H  --    n.m.r. δ = 7.88 (s, NCH) 2.95 (s,                                        NCH.sub.3); 3.60 (q, CH(OCH.sub.2 CH.sub.3).s                                  ub.2); 1.21 (t, CH(OCH.sub.2 CH.sub.3).sub.2)                                  . Molecular weight from mass spectra: 276.        LXXXIV                                                                                ##STR215##   CH.sub.3                                                                          77-80°                                                                        51.716.7423.08 (52.437.1522.93)                   LXXXV                                                                                 ##STR216##   H                                                          LXXXVI                                                                                ##STR217##   H                                                          LXXXVII                                                                               ##STR218##   H        These formamidines were not characterised,                                     being used directly in the preparation of                                      the triazapentadiene product.                     LXXXVIII                                                                              ##STR219##   CH.sub.3                                                   LXXXIX                                                                                ##STR220##   CH.sub.3                                                   XC                                                                                    ##STR221##   CH.sub.3                                                   XCI                                                                                   ##STR222##   H                                                          XCII                                                                                  ##STR223##   H  oil   Not characterised. Used directly in the                                        preparation of the triazapentadiene.              XCIII                                                                                 ##STR224##   H  82-84 64.207.4128.32 (64.407.4328.16)                   XCIV                                                                                  ##STR225##   H  oil   Not characterised. Used directly in the                                        preparation of the triazapentadiene.              XCV                                                                                   ##STR226##   H  82-84 64.417.3728.50 (64.407.4328.16)                   XCVI                                                                                  ##STR227##   H  81-83 71.176.0022.25  (71.335.9922.69)                  __________________________________________________________________________      *The preparation of these compounds is also described in J. Frakt. Chem.,      314, 627 (1972)                                                           

What is claimed is:
 1. A triazapentadiene of the formula: ##STR228## and the acaricidally acceptable acid addition salts thereof, wherein R¹ is alkyl of 1 to 4 carbon atoms;R² is selected from the group consisting of hydrogen, chlorine, bromine, fluorine, iodine and alkyl of 1 to 4 carbon atoms; R³ is benzothiazolyl or thiazolyl optionally containing one or two substituents selected from the group consisting of alkyl of 1 to 4 carbon atoms, alkoxycarbonyl containing 1 to 4 carbon atoms in the alkoxy moiety and unsubstituted phenyl; and R⁴ is hydrogen or alkyl of 1 to 4 carbon atoms.
 2. A triazapentadiene according to claim 1 wherein R¹ is a methyl group.
 3. A triazapentadiene according to claim 1 wherein R² is a methyl group.
 4. A triazapentadiene according to claim 1 wherein R² is a chlorine atom.
 5. An acaricidal composition comprising an acaricidally effective amount of a compound of claim 1 and a diluent or carrier.
 6. A method of combatting ectoparasites on animals, which comprises contacting said animals with an acaricidally effective amount of a compound of claim
 1. 7. 5-(2,4-dimethylphenyl)-3-methyl-1-(6-benzothiazolyl)-1,3,5-triazapenta-1,4-diene.
 8. 5-(2,4-dimethylphenyl)-3-methyl-1-(2-thiazolyl)-1,3,5-triazapenta-1,4-diene. 